maybe you need this
USE_CTIME_FOR_INCREMENTALS bp.conf entry for UNIX clients
The USE_CTIME_FOR_INCREMENTALS entry changes how NetBackup determines
whether or not a file has changed. This entry causes the client software to use
both modification time and inode change time during incremental backups to
determine if a file has changed. (mtime and ctime.)
USE_CTIME_FOR_INCREMENTALS
This entry should appear only once in the bp.conf file.
By default, NetBackup uses only mtime.
Note: If you specify USE_CTIME_FOR_INCREMENTALS, you must also specify
DO_NOT_RESET_FILE_ACCESS_TIME. Do not use these options if Storage Migrator
is on the system. Setting these options causes the file atime to be updated every time
they are backed up. When the atime updates, it appears as if the files are frequently
used and prevents Storage Migrator from selecting the files for migration.
